When compared to standard LED devices, μLEDs may provide advantages of increased extraction efficiency (EE) and a “quasi-collimated” light output, that is, a light output that is at least partially directional. These advantages may be achieved by the introduction of a parabolic mesa structure to the μLED, in which an active layer or light emitting layer sits. Light that is emitted from the light emitting layer is reflected from the internal surface of the mesa and out of the μLED from an emission surface opposed to the mesa. Such a μLED is shown in U.S. Pat. No. 7,518,149.
There is a need for improvements to the μLEDs comprising a mesa structure to provide improved collimation of light.